Thomas kerfoot



' UNITED STATE-s PATENT-OFFICE.

- To'wll whom it may concern.-

. 'rn oMAs KERFO T, OF MANCHESTER, ENGLAND.

METHOD-0F PREPARING t iRANULARIFFERVESCENT communes.

SPECIFICATION forming part of Letters was no. 543,601, dated lT ui so, 1895. Application filed February 10,1898. send r. 461,511. (No-specimens.) Patented iii-EnglandJfn1y )1892,N0-12,998i

Be it known that I, THOMAS Ku'anoor, a citizen of the United Kingdom of Great Britain -and Ireland, residing at Manchester, in the county of LancastenEngland, have invented certain new and useful Improvements in Methods of Preparing Granular Effervesciblo Materials, of which the following is a specification.

This invention has been patented in Great htain July 15, 1892, No. 12,998.

The invention relates to the manufacture of granular etfervescible mixtures, of vwhich a familiar example is that commonly called citrate of magnesia. It is well known that these mixtures are compounds of an acid, such as tartaric or citric acid, and a bicarbonate, such as the bicarbonate of soda, and that their eifervesc'enee upon being mixed Withwater arises from the liberation of carbon dioxid consequent upon the combination of the acid with the alkaline base. a medicinal character or as flavoring or coloring agents are sometimes mixed with the acid and carbonate, and in some cases the acid may be substituted by a. suitable biphosphate or bisulfate. In the usual course of manufacture the moisture contained in the acid produces a reaction and causes the liberation of. some of the carbondioxid, thus reducing the amount of etfervescence when the mixture is finally used. The principalobject of my invention is to avoid this loss, and for this purpose I separately granulateand dry the acid and the alkaline constituents'ot the mixture, which are thereafter intimately mixed and packed in air-tight vessels, suchas are, 5

used for ordinary effervescible mixtures. By

following this method of manufacture no appreciable liberation of carbon dioxid will take place until the mixture is finally used.

I will hereinafiter describe fully'and par ticularly in what manner my invention may be practically carried into efiect; but I'desire it to be understood that I do not limit myself to any particular proportionsof ingredients, to any system of granulation, or mode of drying. My method of manufacture is equally, ap-

plicable to all efiervescible mixtures and compounds which are capable of granulation, and

it may best be illustrated, by way of example,

Other substances of by describing the processes which I adopt in the production of granular effervescent citrate of magnesia, (so-called.) The acid constituent may consist of ten parts of tartaric or of citric acid or of a mixture of them and five parts of sugar, all powdered and intimately mixed together with just: sufficicnt water to make the mixture slightly damp and sticky, so that it will tend to cohcre when pressed together. This mixture is quickly transferred to and rubbed througlf a sieve having about eight meshes to the inch. The granules so formed are then removed to a drying-chamber, which may be heated toabout 100 Fahrenheit, and are called the acid granules. The alkaline constituent may con- 'sist of ten parts of bicarbonate of soda, five parts of powdered sugar, and .two parts of mixture may be mixed, granulated,'and dried in precisely the same manner and by the same means as hereinbefore described for the acid granules, and the granulated product is called the alkaline granules. The acid and the alkaline granules are mixed in such proportions as may be desired and are then bottied for sale and use in the ordinary manner.

Instead of the sugar and water a thin sirup may be employed for damping the powders. Medicinal, flavoring, and coloring agents,

if used, or such of them as may be used, may.

be added to the acid mixture or to the alkaline mixture before or during granulation, or maybe added to the mixed granules as the circumstances in each case may render advisable.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is- 1. In the method of preparing granular effei vescible mixtures, the steps consisting of "sepa rately'submitting the, acid and the alkaline constituents to contact with a saccharine adhesive,-and then granulating anddrying each'constituent before assembling the dried material, substantially as described.

r 2. The.hereinbeforedescribed method of preparing granular efiervescible mixtures, which consists of separately preparing the reacting agents by mixing with'the acid constituent and with the alkaline constituent,

7 dried sulfate of magnesia in powder. This 'suflicient sugar and water to render each mixmy invention I have signed my name, in presture coherent, separately granulating each ence of two witnesses, this 26th day of Janumixture,drying the granules, mixingthe dried ar 1893.

acid and alkaline granules, and packing the 5 mixture in air tight vessels, substantially as Witnesses:

described.

n GEORGE WILLIAM RowE, In testimony that I chain: the foregoing as ARTHUR WILLIAM PULMAN.

THOMAS KERFOOT. 

